Ultrasound has been widely used in clinics. Cellular responses to low-intensity ultrasound are parameter-dependent. Proper parameter setting is vital to its exact use. To get guidelines for parameter setting, lowinten...Ultrasound has been widely used in clinics. Cellular responses to low-intensity ultrasound are parameter-dependent. Proper parameter setting is vital to its exact use. To get guidelines for parameter setting, lowintensity ultrasound stimulation on the proliferation and reproductivity of Hep G2 and 3T3 cells in vitro was examined with a 1.06 MHz-generator by changing the parameters(including intensity, pulse repetition frequency and duty cycle)in a wide range. Cell viability and reproductivity at different time after sonication were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)and colony formation assay to indicate timerelated proliferation. The results illustrate that ultrasound irradiation at 0.4—0.8 W/cm^2 and high pulse repetition frequency(100 Hz)can facilitate cell proliferation, while above 0.8 W/cm^2 would resist it. The extent of resistance closely correlated with duty cycle and pulse repetition frequency. Resistance effect at low pulse repetition frequency(1 Hz)is greater than that at high pulse repetition frequency(100 Hz)and not time-related. The influence of high pulse repetition frequency is time-accumulated, indicating cellular process involved. These findings would provide valuable guidelines for the application of low-intensity ultrasound in stem cell transformation and tissue engineering.展开更多
Sperm concentration of wild yak bull is 2. 13 billion per milliliter. Survival time at 0-4 ℃ is 57hrs. After thawing survival time at 37 ℃ is 12 hrs. Resistance coefficient is 144,000. Abnormal sperm rate and acroso...Sperm concentration of wild yak bull is 2. 13 billion per milliliter. Survival time at 0-4 ℃ is 57hrs. After thawing survival time at 37 ℃ is 12 hrs. Resistance coefficient is 144,000. Abnormal sperm rate and acrosomal integrated rate of post-thawing is 9.17% and 87.53% respectively. Moving viscosity is 1. 169 cp. Total nitrogen is 1 437.7 mg/100 ml. Head of sperm is significantly shorter and end piece is significantly longer than that of domestic yak and yellow cattle. Activity of hyaluronidase is highly stronger than the domestic yak,and the activity of LDH is higher than the domestic yak by 48 %. Hence,the fertility of the wild yak bull is powerful and the artificial inseminated rate with domestic yak and yellow cattle is 88.9% and 71.58% respectively.展开更多
试验旨在探究“2+2”生产模式下不同粗蛋白质水平对白王种鸽繁殖性能和乳鸽生长性能的影响。试验选取产蛋性能相近的300日龄健康种鸽168对,随机分为4组,每组7个重复,每个重复6对种鸽,每对种鸽哺育2只乳鸽。试验Ⅰ组、Ⅱ组、Ⅲ组和Ⅳ组...试验旨在探究“2+2”生产模式下不同粗蛋白质水平对白王种鸽繁殖性能和乳鸽生长性能的影响。试验选取产蛋性能相近的300日龄健康种鸽168对,随机分为4组,每组7个重复,每个重复6对种鸽,每对种鸽哺育2只乳鸽。试验Ⅰ组、Ⅱ组、Ⅲ组和Ⅳ组分别饲喂粗蛋白质水平为13.43%、15.04%、16.64%和18.25%的饲粮。试验期46 d,其中孵化期18 d (1~18 d),哺乳期28 d (19~46 d)。结果显示,试验Ⅱ组、Ⅲ组产蛋间隔显著低于试验Ⅰ组(P<0.05),试验Ⅲ组种蛋受精率显著高于试验Ⅰ组、Ⅳ组(P<0.05),试验Ⅲ组入孵蛋孵化率极显著高于试验Ⅰ组、Ⅱ组、Ⅳ组(P<0.01)。试验Ⅲ组乳鸽28日龄体重显著高于试验Ⅰ组(P<0.05),乳鸽屠宰率极显著高于试验Ⅰ组(P<0.01),乳鸽胸肌率显著高于试验Ⅰ组、Ⅱ组、Ⅳ组(P<0.05)。试验Ⅱ组、Ⅲ组、Ⅳ组窝料重比1极显著低于试验Ⅰ组(P<0.01)。研究表明,不同粗蛋白质水平影响了种鸽的繁殖性能、乳鸽的生长性能以及窝料重比,在“2+2”生产模式下,建议白王种鸽饲粮适宜粗蛋白质水平为16.64%。展开更多
基金Supported by the Natural Science Foundation of Tianjin(No.12JCYBJC18300)
文摘Ultrasound has been widely used in clinics. Cellular responses to low-intensity ultrasound are parameter-dependent. Proper parameter setting is vital to its exact use. To get guidelines for parameter setting, lowintensity ultrasound stimulation on the proliferation and reproductivity of Hep G2 and 3T3 cells in vitro was examined with a 1.06 MHz-generator by changing the parameters(including intensity, pulse repetition frequency and duty cycle)in a wide range. Cell viability and reproductivity at different time after sonication were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)and colony formation assay to indicate timerelated proliferation. The results illustrate that ultrasound irradiation at 0.4—0.8 W/cm^2 and high pulse repetition frequency(100 Hz)can facilitate cell proliferation, while above 0.8 W/cm^2 would resist it. The extent of resistance closely correlated with duty cycle and pulse repetition frequency. Resistance effect at low pulse repetition frequency(1 Hz)is greater than that at high pulse repetition frequency(100 Hz)and not time-related. The influence of high pulse repetition frequency is time-accumulated, indicating cellular process involved. These findings would provide valuable guidelines for the application of low-intensity ultrasound in stem cell transformation and tissue engineering.
文摘Sperm concentration of wild yak bull is 2. 13 billion per milliliter. Survival time at 0-4 ℃ is 57hrs. After thawing survival time at 37 ℃ is 12 hrs. Resistance coefficient is 144,000. Abnormal sperm rate and acrosomal integrated rate of post-thawing is 9.17% and 87.53% respectively. Moving viscosity is 1. 169 cp. Total nitrogen is 1 437.7 mg/100 ml. Head of sperm is significantly shorter and end piece is significantly longer than that of domestic yak and yellow cattle. Activity of hyaluronidase is highly stronger than the domestic yak,and the activity of LDH is higher than the domestic yak by 48 %. Hence,the fertility of the wild yak bull is powerful and the artificial inseminated rate with domestic yak and yellow cattle is 88.9% and 71.58% respectively.
文摘试验旨在探究“2+2”生产模式下不同粗蛋白质水平对白王种鸽繁殖性能和乳鸽生长性能的影响。试验选取产蛋性能相近的300日龄健康种鸽168对,随机分为4组,每组7个重复,每个重复6对种鸽,每对种鸽哺育2只乳鸽。试验Ⅰ组、Ⅱ组、Ⅲ组和Ⅳ组分别饲喂粗蛋白质水平为13.43%、15.04%、16.64%和18.25%的饲粮。试验期46 d,其中孵化期18 d (1~18 d),哺乳期28 d (19~46 d)。结果显示,试验Ⅱ组、Ⅲ组产蛋间隔显著低于试验Ⅰ组(P<0.05),试验Ⅲ组种蛋受精率显著高于试验Ⅰ组、Ⅳ组(P<0.05),试验Ⅲ组入孵蛋孵化率极显著高于试验Ⅰ组、Ⅱ组、Ⅳ组(P<0.01)。试验Ⅲ组乳鸽28日龄体重显著高于试验Ⅰ组(P<0.05),乳鸽屠宰率极显著高于试验Ⅰ组(P<0.01),乳鸽胸肌率显著高于试验Ⅰ组、Ⅱ组、Ⅳ组(P<0.05)。试验Ⅱ组、Ⅲ组、Ⅳ组窝料重比1极显著低于试验Ⅰ组(P<0.01)。研究表明,不同粗蛋白质水平影响了种鸽的繁殖性能、乳鸽的生长性能以及窝料重比,在“2+2”生产模式下,建议白王种鸽饲粮适宜粗蛋白质水平为16.64%。
